1. Field of the Invention
This invention relates to an amplifier circuit in which an additional switching circuit serving to suppress surges is added to a signal amplifier.
2. Description of the Prior Art
Amplifier circuits of the above-noted type are used for amplifying signals, on which disturbing surges (glitches) are superposed. Such surges that superpose on a signal occur, for example, in switching of semiconductor switches by capacitive coupling of the control voltage in the signal path or by lack of synchronization of several parallel switching operations. They occur, for example, at the output of digital-to-analog converters or also at the input of operational amplifiers in case of reversing the feedback impedance.
It is known to make amplifier circuits, which include a dc negative feedback signal amplifier connected to a surge suppressing switching circuit, for subsequent processing of the output signal of a digital-to-analog converter, with sample and hold elements, which are connected in series with the signal amplifier and, controlled by a clock signal, blank out the signal received at the output of the digital-to-analog converter during any period in which surges can occur (S. Kirby: Deglitcher circuit refines d-a-converter output; Electronics, 4/21/1983, pp 151-152).
With these types of amplifier circuits an external control of the switching circuit serving to suppress the surges is necessary, which limits the possibilities of using the circuit and, moreover, in the context of the possible field of application causes considerable circuit complexity. Further, the fast sample and hold elements necessary for high sampling rates themselves produce disturbing surges, which, for example, in the amplification of the output signal of fast digital-to-analog converters appears as very disturbing.